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    <H1 CLASS="title">Class Template <CODE>back_insert_device</CODE></H1>
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  <DT><A href="#description">Description</A></DT>
  <DT><A href="#headers">Headers</A></DT>
  <DT><A href="#synopsis">Synopsis</A></DT>
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<A NAME="description"></A>
<H2>Description</H2>

<P>
    The header <A CLASS="header" HREF="../../../../boost/iostreams/device/back_inserter.hpp"><CODE>&lt;boost/iostreams/device/back_inserter.hpp&gt;</CODE></A> contains the definition of the class template <CODE>back_insert_device</CODE> &#8212; implementing a <A HREF="../concepts/sink.html">Sink</A> which appends to a standard library sequence container &#8212; as well as the definition of a corresponding object generator, the function template <CODE>boost::iostreams::back_inserter</CODE>.
</P>

<P>
    The Iostream Library allows OutputIterators to be used in many places where <A HREF="../concepts/sink.html">Sinks</A> are allowed. However, using <CODE>boost::iostreams::back_inserter</CODE> my be somewhat more efficient than using <CODE>std::back_inserter</CODE>, since the former uses the function <CODE>insert</CODE> to append a sequence of characters in one operation. Furthermore, <CODE>std::back_insert_iterator</CODE> is not strictly a model of <A HREF="../concepts/sink.html">Sink</A>, so one can write
</P>

<PRE CLASS="broken_ie"><SPAN CLASS="keyword">namespace</SPAN> io = boost::iostreams;

<SPAN CLASS="keyword">typedef</SPAN> io::stream&lt; io::back_insert_device&lt;std::string&gt; &gt; my_stream</PRE>

<P>But not</P>

<PRE CLASS="broken_ie"><SPAN CLASS="keyword">typedef</SPAN> io::stream&lt; std::back_insert_iterator&lt;std::string&gt; &gt; my_stream</PRE>

<A NAME="headers"></A>
<H2>Headers</H2>

<DL>
  <DT><A CLASS="header" HREF="../../../../boost/iostreams/device/back_inserter.hpp"><CODE>&lt;boost/iostreams/device/back_inserter.hpp&gt;</CODE></A></DT>
</DL>

<A NAME="synopsis"></A>
<H2>Synopsis</H2>

<PRE CLASS="broken_ie"><SPAN CLASS="keyword">namespace</SPAN> boost { <SPAN CLASS="keyword">namespace</SPAN> iostreams {

<SPAN CLASS="keyword">template</SPAN>&lt;<SPAN CLASS="keyword">typename</SPAN> <A HREF="#back_insert_device_template_params" CLASS="documented">Container</A>&gt;
<SPAN CLASS="keyword">class</SPAN> <A HREF="#back_insert_device_template_params" CLASS="documented">back_insert_device</A> {
<SPAN CLASS="keyword">public</SPAN>:
    <SPAN CLASS="keyword">typedef</SPAN> <SPAN CLASS="keyword">typename</SPAN> Container::value_type  char_type;
    <SPAN CLASS="keyword">typedef</SPAN> sink_tag                        category;
    <A HREF="#back_insert_device_constructor" CLASS="documented">back_insert_device</A>(Container&amp; cnt);
    <SPAN CLASS="omitted">...</SPAN> 
};

<SPAN CLASS="keyword">template</SPAN>&lt;<SPAN CLASS="keyword">typename</SPAN> <A HREF="#back_insert_device_template_params" CLASS="documented">Container</A>&gt;
<A CLASS="documented" HREF="#back_insert_device_template_params">back_insert_device</A>&lt;Container&gt; <A CLASS="documented" HREF="#back_inserter">back_inserter</A>(Container&amp; cnt);

} } <SPAN CLASS="comment">// End namespace boost::io</SPAN></PRE>

<A NAME="back_insert_device_template_params"></A>
<H4>Template Parameters</H4>

<TABLE STYLE="margin-left:2em" BORDER=0 CELLPADDING=2>
<TR>
    <TR>
        <TD VALIGN="top"><I>Container</I></TD><TD WIDTH="2em" VALIGN="top">-</TD>
        <TD>A C++ standard library sequence type (<A CLASS="bib_ref" HREF="../bibliography.html#iso">[ISO]</A>, 23.1.1).
    </TR>
</TABLE>

<A NAME="back_insert_device_constructor"></A>
<H4><CODE>back_insert_device::back_insert_device</CODE></H4>

<PRE CLASS="broken_ie">    back_insert_device(Container&amp; cnt);</PRE>

<P>Constructs an instance of <CODE>back_insert_device</CODE> for appending to the given container. The given reference must remain valid for the lifetime of the instance of <CODE>back_insert_device</CODE>.</P>

<A NAME="back_inserter"></A>
<H4><CODE>back_inserter</CODE></H4>

<PRE CLASS="broken_ie"><SPAN CLASS="keyword">template</SPAN>&lt;<SPAN CLASS="keyword">typename</SPAN> Container&gt;
back_insert_device&lt;Container&gt; back_inserter(Container&amp; cnt);</PRE>

<P>Returns an instance of <CODE>back_insert_device</CODE> for appending to the given container.</P>

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    Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at <A HREF="http://www.boost.org/LICENSE_1_0.txt">http://www.boost.org/LICENSE_1_0.txt</A>)
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